BOGOTA, Colombia — When Colombians talk about a national drug problem, it’s sometimes not cocaine or heroin they mean. It’s burundanga.A tasteless and odorless powder, burundanga sends those who consume it into a voodoo-like trance. Dozens of times each week, somewhere in Colombia, a criminal sprinkles the soluble powder into the food or drink of a victim, then waits for the person to turn into a disoriented zombie — awake and talkative but powerless to resist orders.

Criminals then tell their victims to make bank withdrawals, hand over their car keys and clothing, perhaps deliver narcotics, or even help empty their own apartments of furniture.

What’s more, under the effects of burundanga, victims suffer temporary amnesia. The hard drive in their brain goes blank until the drug wears off.

“A lot of times, the victim can’t even remember what the criminal looks like. So it’s very difficult to arrest anyone,” said Dr. Camilo Uribe, a toxicologist and Colombia’s premier expert on the substance.

In the 1960s, when crooks began using burundanga, they picked out victims in bus terminals or seedy bars. But nowadays, no one is safe from the drug. Among victims in the past year are a state governor, prominent lawyers, entire families doped up by their maids, and thousands of other victims.

“Everybody knows somebody who’s been given this drug,” said Elkin Osorio, an epidemiologist with the Bogota city health department.

Burundanga is so common that a State Department travel advisory warns of it: “The drug is administered in drinks in bars, through cigarettes and gum in taxis, and in powder form. … The drug renders the person disoriented and can cause prolonged unconsciousness and serious medical problems.”

In Bogota alone, a capital of 6.5 million people, hospitals go through 8,500 kits a year to test for chemical intoxication, Osorio said. He added that many of those cases turn out to be burundanga. Asked whether Bogota might have 1,000 cases a month, he said, “It’s a lot higher. You can be sure.”

Uribe estimated that Colombia’s largest cities have hundreds of cases a month. Other experts offered lower estimates. But they noted that many victims never report to authorities.

Colombia is alone with the problem. Burundanga has been reported in Ecuador and Venezuela, but criminals there seem to fear the substance, which can permanently impair or kill victims. If mishandled, it muddles up the crook instead of the victim.

Burundanga has been around since before the discovery of the New World. Its active ingredient, scopolamine, is found in a plant from the nightshade family known as borrachera (drunken binge), which grows in the high Andes.

“Here in Bogota, you can find it in the parks,” Uribe said, adding that most criminals now use laboratory-produced scopolamine from the black market.

Scopolamine can make users extremely aggressive, so criminals in the 1980s began mixing it with other drugs, like tranquilizers. Colombians know the chemical cocktail as burundanga — pronounced boo-roon-DAHN-gah — and inventive criminals offer it orally, mixed with gaseous substances or even apparently as a powder in cigarettes.

Taxi drivers say victims sometimes flag them down in a trance.

“We call them `the disoriented ones,”’ said Omar Echavarria, a taxi driver in Medellin, Colombia’s third-largest city. “They get in the taxi, and you ask them where they are going. They say they don’t know. They don’t even know who they are. They get in a taxi out of instinct.”

When doped-up passengers arrive at hospital emergency rooms for treatment, doctors normally give them diuretics to flush out their kidneys. Those who received small doses of the drug usually recover within a half-day.

What happened to Erick Schaffer is a common story. Schaffer, a Nicaraguan, walked into a discotheque along well-traveled Seventh Avenue one night a few months ago. After that, his memory is blank.

“The next day, I came to,” Schaffer said. “A doorman was trying to open the garage door of an apartment building, and it woke me. I was sitting down on the sidewalk in a daze. He took me to my apartment.”

Schaffer said the criminals spent about $1,000 on one of his credit cards.

Now, he tells visitors: “Don’t go to the bathroom and leave your beer or they may toss in the drug. … Don’t accept soft drinks or buy cigarettes on the street. Or candy. Or anything else.”

The use of burundanga is so common — and Colombia so ridden by violence — that such robberies almost never make the newspapers.

An exception occurred when Juan Carlos Vives, governor of Magdalena, one of Colombia’s 33 states, was slipped burundanga at Bogota’s fanciest mall, the Centro Andino, last April.

“Two men came up to me and asked for the time. I don’t remember their faces or anything after that,” the 44-year-old Vives said. He led the men to his apartment. “I don’t remember it, but the doormen say that I entered the apartment with them.”

He said he regained consciousness the next day to discover that the men had stolen about $7,000, all his credit cards, some jewelry, a guitar “and even my reading glasses,” Vives said.

Colombians sometimes aren’t safe even in their own homes.

Mauricio Velasquez, 18, sat down to lunch with his brother, sister and mother in their Medellin home 11 months ago. A young housekeeper hired 10 days earlier served them rice and beans.

“When we got up, I passed out,” he said. So did his mother, Marina, and a 14-year-old brother, Andres Felipe. Luckily, a sister, Paula Andrea, 18, ate little. Semi-conscious, she dialed a boyfriend on a cellular telephone.

“The boyfriend came, saw what had happened and locked up the housekeeper,” Velasquez said. He said police arrested the housekeeper and an accomplice, and determined that their plan was to clean the house of jewelry.

Many victims never go to the authorities. Some realize they don’t know who slipped them the drug. Others feel embarrassed over what happened.

“I’d say 70 percent of the cases are never reported,” said Jairo Martinez, an expert at Colombia’s equivalent of the FBI. “People are ashamed they didn’t take security measures. Or they were somewhere they shouldn’t have been, like a brothel.”

Burundanga-bearing criminals lurk around airports, bus terminals and popular bars, or go door-to-door pretending to be salespeople, persuading housewives to take whiffs of products containing the powder and some sort of gaseous admixture.

Scantily clad women frequenting bars sometimes slip burundanga into drinks of unsuspecting men — giving them a time they’ll never remember.

Even criminals fall victim.

In a case in 1996, six people came into Medellin’s Las Vegas Clinic in a daze, waylaid by illness on the way to the airport, Dr. Hugo Gallego, a prominent Medellin toxicologist, said. Hours later, one vomited up a capsule filled with cocaine. All six were “mules,” and someone had drugged them with the hope of commandeering the narcotics-packed capsules, Gallego added.

Ever inventive, some Colombians have turned the burundanga epidemic to their favor. Philandering husbands sometimes wander into hospitals for tests after spending days with girlfriends, eager for a plausible excuse to explain away their absence on the home front.

“It’s simply a way for them to go home and not have any problems,” said Dr. Sergio Alvarez, an emergency-room physician in Medellin.